<template>
  <div class="box">
    <div class="header">
      <div class="h_logo" :style="!isCollapse ? 'width:200px' : 'width:64px'">
        <i v-if="isCollapse" class="el-icon-eleme"></i>
        <i v-else class="el-icon-platform-eleme">ZZ</i>
      </div>
      <div class="h_menu_btn">
        <el-button
          size="small"
          @click="isCollapse = !isCollapse"
          type="primary"
          :icon="isCollapse ? 'el-icon-s-unfold' : 'el-icon-s-fold'"
        ></el-button>
      </div>
      <div class="h_title">
        vue-element ui 简易后台管理系统
        <el-dropdown @command="out">
          <span class="el-dropdown-link">
            菜单<i class="el-icon-arrow-down el-icon--right"></i>
          </span>
          <el-dropdown-menu slot="dropdown">
            <el-dropdown-item command="1">设置</el-dropdown-item>
            <el-dropdown-item command="2" divided>退出</el-dropdown-item>
          </el-dropdown-menu>
        </el-dropdown>
      </div>
    </div>
    <div class="body">
      <div class="nav">
        <el-menu
          :unique-opened="true"
          :default-active="active"
          class="el-menu-vertical-demo"
          @open="handleOpen"
          background-color="#545c64"
          text-color="#fff"
          active-text-color="#ffd04b"
          @close="handleClose"
          :collapse="isCollapse"
          @select="handleSelect"
        >
          <el-menu-item index="首页">
            <i class="el-icon-s-home"></i>
            <span slot="title">首页</span>
          </el-menu-item>

          <el-submenu index="数据表格">
            <template slot="title">
              <i class="el-icon-menu"></i>
              <span slot="title">数据表格</span>
            </template>
            <el-menu-item-group index="数据表格">
              <el-menu-item index="使用说明" data-path="/index/page1"
                >使用说明</el-menu-item
              >
              <el-menu-item index="普通表格" data-path="/index/page2"
                >普通表格</el-menu-item
              >
              <el-menu-item index="文档预览" data-path="/index/page3"
                >文档预览</el-menu-item
              >
            </el-menu-item-group>
            <el-submenu index="打印/下载">
              <span slot="title">打印/下载</span>
              <el-menu-item index="打印/下载" data-path="/index/page4"
                >打印/下载</el-menu-item
              >
            </el-submenu>
          </el-submenu>
          <el-submenu index="可视化">
            <template slot="title">
              <i class="el-icon-s-data"></i>
              <span slot="title">可视化</span>
            </template>
            <el-menu-item-group index="可视化">
              <el-menu-item index="扇形图" data-path="/index/page5"
                >扇形图</el-menu-item
              >
              <el-menu-item index="条形图" data-path="/index/page6"
                >条形图</el-menu-item
              >
            </el-menu-item-group>
          </el-submenu>

          <el-menu-item index="3" disabled>
            <i class="el-icon-document"></i>
            <span slot="title">导航三</span>
          </el-menu-item>
        </el-menu>
      </div>
      <div class="main" ref="main">
        <div class="breadcrumb" ref="breadcrumb">
          <el-breadcrumb separator-class="el-icon-arrow-right">
            <el-breadcrumb-item :to="{ path: '/index/page1' }"
              >首页</el-breadcrumb-item
            >
            <template v-for="(item, index) in breadcrumbs">
              <el-breadcrumb-item :key="index">{{ item }}</el-breadcrumb-item>
            </template>
          </el-breadcrumb>
        </div>
        <div
          class="content"
          :key="contenteight"
          :style="{ height: contenteight + 'px' }"
        >
          <router-view></router-view>
        </div>
        <div class="foot" ref="foot">Copyright© 2021</div>
      </div>
    </div>
  </div>
</template>
<script>
export default {
  data() {
    return {
      active: "首页", // 默认选择
      breadcrumbs: ["首页"],
      isCollapse: false,
      navMap: new Map([
        ["首页", "/index/index"],
        ["使用说明", "/index/page1"],
        ["普通表格", "/index/page2"],
        ["文档预览", "/index/page3"],
        ["打印/下载", "/index/page4"],
        ["扇形图", "/index/page5"],
        ["条形图", "/index/page6"],
      ]),
      contenteight: "",
    };
  },

  mounted() {
    this.$router.push("/index/index");
    this.$nextTick(() => {
      let mainheight = this.$refs.main.offsetHeight;
      let breadcrumbheight = this.$refs.breadcrumb.offsetHeight;
      let footheight = this.$refs.foot.offsetHeight;
      this.contenteight = mainheight - breadcrumbheight - footheight;
    });
  },
  methods: {
    // 3个导航栏事件
    handleOpen() {
      // this.breadcrumbs = keyPath;
      // console.log(key, keyPath);
      // console.log("Open");
    },
    handleClose() {
      // this.breadcrumbs = keyPath;
      // console.log(key, keyPath);
      // console.log("Close");
    },
    handleSelect(index, indexPath) {
      this.breadcrumbs = indexPath;
      // console.log(index, indexPath);
      this.$router.push(this.navMap.get(index));
    },
    // 退出
    out(val) {
      console.log(val);
      if (val == 2) {
        this.$router.push("/");
      }
    },
  },
};
</script>
<style scoped lang="less">
.box {
  height: 100%;
  box-sizing: border-box;
}
.header {
  height: 60px;
  line-height: 60px;
  font-size: 16px;
  background: #409eff;
  color: white;
  display: flex;
  text-align: center;
  .h_logo {
    transition: width 0.3s;
    transition-timing-function: ease-in-out;
    background: rgb(102, 177, 255);
    font-size: 30px;
  }
  .h_menu_btn {
    width: 64px;
    font-size: 16px;
    .el-button--small {
      padding: 5px 8px;
      font-size: 16px;
    }
  }
  .h_title {
    flex: 1;
    position: relative;
    .el-dropdown {
      position: absolute;
      right: 20px;
      color: white;
    }
  }
}
.body {
  position: absolute;
  width: 100%;
  top: 60px;
  bottom: 0px;
  display: flex;
  box-sizing: border-box;
  .nav {
    background: #545c64;
    overflow: auto;
    .el-menu {
      border-right: none;
    }
    .el-menu-vertical-demo:not(.el-menu--collapse) {
      width: 200px;
      min-height: 400px;
    }
  }
  .main {
    flex: 1;
    background: #ebeef5;
    position: relative;
    overflow: hidden;
    .breadcrumb {
      box-sizing: border-box;
      background: white;
      padding: 10px;
    }
    .content {
      padding: 5px;
      box-sizing: border-box;
    }
    .foot {
      height: 30px;
      line-height: 30px;
      position: absolute;
      bottom: 0;
      background: white;
      text-align: center;
      width: 100%;
      font-size: 12px;
    }
  }
}
</style>